Create a workflow which tests out the full set of daq-buildtools features

[jcfreeman2]

This was a suggestion from @bieryAtFnal after he discovered last night that dbt-clang-format.sh stopped working. The script's call to spack load llvm only works if there's a single version of llvm installed on /cvmfs, whereas yesterday I'd installed a second version for testing purposes. The idea would be to be able to programmatically regression test the suite of tools offered by daq-buildtools, with a message being sent to the #daq-release-notifications channel if something went wrong.